A rickettsial disease, also known as cowdriosis, which is caused by the microorganism Cowdria ruminantium and is transmitted by ticks of the genus Amblyomma. The disease occurs in wild and domestic ruminants, primarily cattle, sheep, and goats, in sub-Saharan Africa and some Caribbean islands (for example, Guadeloupe, Antigua, and Marie-Galante). Heartwater disease is characterized by fluid in the pericardium of the heart, high fever, lung edema, and nervous symptoms that range from mild incoordination and exaggerated reflexes to convulsions seen in acute infections. The course of acute heartwater disease is 2–6 days, and recovery is rare. However, young animals have a high rate of natural resistance. The organism is susceptible to tetracycline antibiotics. However, once marked nervous symptoms have developed, recovery usually does not occur. Control and prevention of heartwater is achieved by tick control or immunization. |
